1. The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan.

2. The price reported in Column 4 is a weighted average price. These Common Units were purchased in multiple transactions at prices ranging from $5.12 to $5.44, excluding commissions. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Units purchased at each separate price within the range set forth in this footnote.

3. The price reported in Column 4 is a weighted average price. These Common Units were purchased in multiple transactions at prices ranging from $4.90 to $5.37, excluding commissions. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Units purchased at each separate price within the range set forth in this footnote.

4. The price reported in Column 4 is a weighted average price. These Common Units were purchased in multiple transactions at prices ranging from $4.85 to $5.11, excluding commissions. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Units purchased at each separate price within the range set forth in this footnote.

/s/ Maria Reda as attorney-in-fact for Gordon A. Walker

04/03/2020

** Signature of Reporting Person

Date

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person,
see
Instruction
4
(b)(v).